ib_mi.c

Go to the documentation of this file.

/*
 * Copyright (C) 2009 Michael Brown <mbrown@fensystems.co.uk>.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation; either version 2 of the
 * License, or any later version.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

FILE_LICENCE ( GPL2_OR_LATER );

#include <stdint.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <stdio.h>
#include <unistd.h>
#include <byteswap.h>
#include <gpxe/infiniband.h>
#include <gpxe/iobuf.h>
#include <gpxe/ib_mi.h>

/**
 * @file
 *
 * Infiniband management interfaces
 *
 */

/** Management interface number of send WQEs
 *
 * This is a policy decision.
 */
#define IB_MI_NUM_SEND_WQES 4

/** Management interface number of receive WQEs
 *
 * This is a policy decision.
 */
#define IB_MI_NUM_RECV_WQES 2

/** Management interface number of completion queue entries
 *
 * This is a policy decision
 */
#define IB_MI_NUM_CQES 8

/** TID magic signature */
#define IB_MI_TID_MAGIC ( ( 'g' << 24 ) | ( 'P' << 16 ) | ( 'X' << 8 ) | 'E' )

/** TID to use for next MAD */
static unsigned int next_tid;

/**
 * Handle received MAD
 *
 * @v ibdev             Infiniband device
 * @v mi                Management interface
 * @v mad               Received MAD
 * @v av                Source address vector
 * @ret rc              Return status code
 */
static int ib_mi_handle ( struct ib_device *ibdev,
                          struct ib_mad_interface *mi,
                          union ib_mad *mad,
                          struct ib_address_vector *av ) {
        struct ib_mad_hdr *hdr = &mad->hdr;
        struct ib_mad_transaction *madx;
        struct ib_mad_agent *agent;

        /* Look for a matching transaction by TID */
        list_for_each_entry ( madx, &mi->madx, list ) {
                if ( memcmp ( &hdr->tid, &madx->mad.hdr.tid,
                              sizeof ( hdr->tid ) ) != 0 )
                        continue;
                /* Found a matching transaction */
                madx->op->complete ( ibdev, mi, madx, 0, mad, av );
                return 0;
        }

        /* If there is no matching transaction, look for a listening agent */
        for_each_table_entry ( agent, IB_MAD_AGENTS ) {
                if ( ( ( agent->mgmt_class & IB_MGMT_CLASS_MASK ) !=
                       ( hdr->mgmt_class & IB_MGMT_CLASS_MASK ) ) ||
                     ( agent->class_version != hdr->class_version ) ||
                     ( agent->attr_id != hdr->attr_id ) )
                        continue;
                /* Found a matching agent */
                agent->handle ( ibdev, mi, mad, av );
                return 0;
        }

        /* Otherwise, ignore it */
        DBGC ( mi, "MI %p RX TID %08x%08x ignored\n",
               mi, ntohl ( hdr->tid[0] ), ntohl ( hdr->tid[1] ) );
        return -ENOTSUP;
}

/**
 * Complete receive via management interface
 *
 *
 * @v ibdev             Infiniband device
 * @v qp                Queue pair
 * @v av                Address vector
 * @v iobuf             I/O buffer
 * @v rc                Completion status code
 */
static void ib_mi_complete_recv ( struct ib_device *ibdev,
                                  struct ib_queue_pair *qp,
                                  struct ib_address_vector *av,
                                  struct io_buffer *iobuf, int rc ) {
        struct ib_mad_interface *mi = ib_qp_get_ownerdata ( qp );
        union ib_mad *mad;
        struct ib_mad_hdr *hdr;

        /* Ignore errors */
        if ( rc != 0 ) {
                DBGC ( mi, "MI %p RX error: %s\n", mi, strerror ( rc ) );
                goto out;
        }

        /* Sanity checks */
        if ( iob_len ( iobuf ) != sizeof ( *mad ) ) {
                DBGC ( mi, "MI %p RX bad size (%zd bytes)\n",
                       mi, iob_len ( iobuf ) );
                DBGC_HDA ( mi, 0, iobuf->data, iob_len ( iobuf ) );
                goto out;
        }
        mad = iobuf->data;
        hdr = &mad->hdr;
        if ( hdr->base_version != IB_MGMT_BASE_VERSION ) {
                DBGC ( mi, "MI %p RX unsupported base version %x\n",
                       mi, hdr->base_version );
                DBGC_HDA ( mi, 0, mad, sizeof ( *mad ) );
                goto out;
        }
        DBGC ( mi, "MI %p RX TID %08x%08x (%02x,%02x,%02x,%04x) status "
               "%04x\n", mi, ntohl ( hdr->tid[0] ), ntohl ( hdr->tid[1] ),
               hdr->mgmt_class, hdr->class_version, hdr->method,
               ntohs ( hdr->attr_id ), ntohs ( hdr->status ) );
        DBGC2_HDA ( mi, 0, mad, sizeof ( *mad ) );

        /* Handle MAD */
        if ( ( rc = ib_mi_handle ( ibdev, mi, mad, av ) ) != 0 )
                goto out;

 out:
        free_iob ( iobuf );
}

/** Management interface completion operations */
static struct ib_completion_queue_operations ib_mi_completion_ops = {
        .complete_recv = ib_mi_complete_recv,
};

/**
 * Transmit MAD
 *
 * @v ibdev             Infiniband device
 * @v mi                Management interface
 * @v mad               MAD
 * @v av                Destination address vector
 * @ret rc              Return status code
 */
int ib_mi_send ( struct ib_device *ibdev, struct ib_mad_interface *mi,
                 union ib_mad *mad, struct ib_address_vector *av ) {
        struct ib_mad_hdr *hdr = &mad->hdr;
        struct io_buffer *iobuf;
        int rc;

        /* Set common fields */
        hdr->base_version = IB_MGMT_BASE_VERSION;
        if ( ( hdr->tid[0] == 0 ) && ( hdr->tid[1] == 0 ) ) {
                hdr->tid[0] = htonl ( IB_MI_TID_MAGIC );
                hdr->tid[1] = htonl ( ++next_tid );
        }
        DBGC ( mi, "MI %p TX TID %08x%08x (%02x,%02x,%02x,%04x) status "
               "%04x\n", mi, ntohl ( hdr->tid[0] ), ntohl ( hdr->tid[1] ),
               hdr->mgmt_class, hdr->class_version, hdr->method,
               ntohs ( hdr->attr_id ), ntohs ( hdr->status ) );
        DBGC2_HDA ( mi, 0, mad, sizeof ( *mad ) );

        /* Construct directed route portion of response, if necessary */
        if ( hdr->mgmt_class == IB_MGMT_CLASS_SUBN_DIRECTED_ROUTE ) {
                struct ib_mad_smp *smp = &mad->smp;
                unsigned int hop_pointer;
                unsigned int hop_count;

                smp->mad_hdr.status |= htons ( IB_SMP_STATUS_D_INBOUND );
                hop_pointer = smp->mad_hdr.class_specific.smp.hop_pointer;
                hop_count = smp->mad_hdr.class_specific.smp.hop_count;
                assert ( hop_count == hop_pointer );
                if ( hop_pointer < ( sizeof ( smp->return_path.hops ) /
                                     sizeof ( smp->return_path.hops[0] ) ) ) {
                        smp->return_path.hops[hop_pointer] = ibdev->port;
                } else {
                        DBGC ( mi, "MI %p TX TID %08x%08x invalid hop pointer "
                               "%d\n", mi, ntohl ( hdr->tid[0] ),
                               ntohl ( hdr->tid[1] ), hop_pointer );
                        return -EINVAL;
                }
        }

        /* Construct I/O buffer */
        iobuf = alloc_iob ( sizeof ( *mad ) );
        if ( ! iobuf ) {
                DBGC ( mi, "MI %p could not allocate buffer for TID "
                       "%08x%08x\n",
                       mi, ntohl ( hdr->tid[0] ), ntohl ( hdr->tid[1] ) );
                return -ENOMEM;
        }
        memcpy ( iob_put ( iobuf, sizeof ( *mad ) ), mad, sizeof ( *mad ) );

        /* Send I/O buffer */
        if ( ( rc = ib_post_send ( ibdev, mi->qp, av, iobuf ) ) != 0 ) {
                DBGC ( mi, "MI %p TX TID %08x%08x failed: %s\n",
                       mi,  ntohl ( hdr->tid[0] ), ntohl ( hdr->tid[1] ),
                       strerror ( rc ) );
                free_iob ( iobuf );
                return rc;
        }

        return 0;
}

/**
 * Handle management transaction timer expiry
 *
 * @v timer             Retry timer
 * @v expired           Failure indicator
 */
static void ib_mi_timer_expired ( struct retry_timer *timer, int expired ) {
        struct ib_mad_transaction *madx =
                container_of ( timer, struct ib_mad_transaction, timer );
        struct ib_mad_interface *mi = madx->mi;
        struct ib_device *ibdev = mi->ibdev;
        struct ib_mad_hdr *hdr = &madx->mad.hdr;

        /* Abandon transaction if we have tried too many times */
        if ( expired ) {
                DBGC ( mi, "MI %p abandoning TID %08x%08x\n",
                       mi, ntohl ( hdr->tid[0] ), ntohl ( hdr->tid[1] ) );
                madx->op->complete ( ibdev, mi, madx, -ETIMEDOUT, NULL, NULL );
                return;
        }

        /* Restart retransmission timer */
        start_timer ( timer );

        /* Resend MAD */
        ib_mi_send ( ibdev, mi, &madx->mad, &madx->av );
}

/**
 * Create management transaction
 *
 * @v ibdev             Infiniband device
 * @v mi                Management interface
 * @v mad               MAD to send
 * @v av                Destination address, or NULL to use SM's GSI
 * @v op                Management transaction operations
 * @ret madx            Management transaction, or NULL
 */
struct ib_mad_transaction *
ib_create_madx ( struct ib_device *ibdev, struct ib_mad_interface *mi,
                 union ib_mad *mad, struct ib_address_vector *av,
                 struct ib_mad_transaction_operations *op ) {
        struct ib_mad_transaction *madx;

        /* Allocate and initialise structure */
        madx = zalloc ( sizeof ( *madx ) );
        if ( ! madx )
                return NULL;
        madx->mi = mi;
        madx->timer.expired = ib_mi_timer_expired;
        madx->op = op;

        /* Determine address vector */
        if ( av ) {
                memcpy ( &madx->av, av, sizeof ( madx->av ) );
        } else {
                madx->av.lid = ibdev->sm_lid;
                madx->av.sl = ibdev->sm_sl;
                madx->av.qpn = IB_QPN_GSI;
                madx->av.qkey = IB_QKEY_GSI;
        }

        /* Copy MAD */
        memcpy ( &madx->mad, mad, sizeof ( madx->mad ) );

        /* Add to list and start timer to send initial MAD */
        list_add ( &madx->list, &mi->madx );
        start_timer_nodelay ( &madx->timer );

        return madx;
}

/**
 * Destroy management transaction
 *
 * @v ibdev             Infiniband device
 * @v mi                Management interface
 * @v madx              Management transaction
 */
void ib_destroy_madx ( struct ib_device *ibdev __unused,
                       struct ib_mad_interface *mi __unused,
                       struct ib_mad_transaction *madx ) {

        /* Stop timer and remove from list */
        stop_timer ( &madx->timer );
        list_del ( &madx->list );

        /* Free transaction */
        free ( madx );
}

/**
 * Create management interface
 *
 * @v ibdev             Infiniband device
 * @v type              Queue pair type
 * @ret mi              Management agent, or NULL
 */
struct ib_mad_interface * ib_create_mi ( struct ib_device *ibdev,
                                         enum ib_queue_pair_type type ) {
        struct ib_mad_interface *mi;
        int rc;

        /* Allocate and initialise fields */
        mi = zalloc ( sizeof ( *mi ) );
        if ( ! mi )
                goto err_alloc;
        mi->ibdev = ibdev;
        INIT_LIST_HEAD ( &mi->madx );

        /* Create completion queue */
        mi->cq = ib_create_cq ( ibdev, IB_MI_NUM_CQES, &ib_mi_completion_ops );
        if ( ! mi->cq ) {
                DBGC ( mi, "MI %p could not allocate completion queue\n", mi );
                goto err_create_cq;
        }

        /* Create queue pair */
        mi->qp = ib_create_qp ( ibdev, type, IB_MI_NUM_SEND_WQES, mi->cq,
                                IB_MI_NUM_RECV_WQES, mi->cq );
        if ( ! mi->qp ) {
                DBGC ( mi, "MI %p could not allocate queue pair\n", mi );
                goto err_create_qp;
        }
        ib_qp_set_ownerdata ( mi->qp, mi );
        DBGC ( mi, "MI %p (%s) running on QPN %#lx\n",
               mi, ( ( type == IB_QPT_SMI ) ? "SMI" : "GSI" ), mi->qp->qpn );

        /* Set queue key */
        mi->qp->qkey = ( ( type == IB_QPT_SMI ) ? IB_QKEY_SMI : IB_QKEY_GSI );
        if ( ( rc = ib_modify_qp ( ibdev, mi->qp ) ) != 0 ) {
                DBGC ( mi, "MI %p could not set queue key: %s\n",
                       mi, strerror ( rc ) );
                goto err_modify_qp;
        }

        /* Fill receive ring */
        ib_refill_recv ( ibdev, mi->qp );
        return mi;

 err_modify_qp:
        ib_destroy_qp ( ibdev, mi->qp );
 err_create_qp:
        ib_destroy_cq ( ibdev, mi->cq );
 err_create_cq:
        free ( mi );
 err_alloc:
        return NULL;
}

/**
 * Destroy management interface
 *
 * @v mi                Management interface
 */
void ib_destroy_mi ( struct ib_device *ibdev, struct ib_mad_interface *mi ) {
        struct ib_mad_transaction *madx;
        struct ib_mad_transaction *tmp;

        /* Flush any outstanding requests */
        list_for_each_entry_safe ( madx, tmp, &mi->madx, list ) {
                DBGC ( mi, "MI %p destroyed while TID %08x%08x in progress\n",
                       mi, ntohl ( madx->mad.hdr.tid[0] ),
                       ntohl ( madx->mad.hdr.tid[1] ) );
                madx->op->complete ( ibdev, mi, madx, -ECANCELED, NULL, NULL );
        }

        ib_destroy_qp ( ibdev, mi->qp );
        ib_destroy_cq ( ibdev, mi->cq );
        free ( mi );
}